Method of and apparatus for generating combustible gas and coke



Nov; 18,1930. H FSWH v 1,781,166

METHOD oF AND vAPPAlwvus FOR GENERATNG COMBUSTIBLE GAS ANDVCOKE Filedsept'. 9, 1922 f @723255555 I ZH/@UTUT- Patented Novh 18, 1930 HARRYF.SMITH, OE DAYTON,

OHIO, ASSIGNOR TO THE GAS RESEARCH COMPANY, 0Fl

-DAYTON, OHIO, jA CORPORATION or OHIO METHOD OF AND APPARATUS FORGENERATING COMBUSTIBLE GAS AND COKE Applicationvfued september 9, 1922.kserial No. 587,075.

i This invention relates to the production of a combustible gas andofcoke or charcoal from carbonaceous fuel such as coal, wood, peat andthe'like. f

One of the principal Objects of theinvention is to provide a method forcontinuously producing acombustible gas,.and at the same time .producingcoke or charcoal.

Another object of the invention is to provide a method of producing acombustible gas which is in water gas-coal gas-producer gas method.v

Another object of the invention is to provide a method of making acombustible gas from carbonaceous material in which the character of thegas generated may be controlled to give a gas ofidesired composition andheating'valaie.

Still anotherl object of the invention is to provide an improved form ofapparatus for carrying this method into effect.

.A Other objects and advantages of the invention-will be apparent fromthe description means of a top 12 and set out below when taken inconnection with the accompanying drawing.; in which is illustrated insection, and somewhat diagrammatioally, a form of apparatus for carryingout a method of gas and coke making according to this invention. A

This apparatus consists essentially of a metallic shell 10,'supportedupon suitable foundations ll, its upper end being closed by its lowerend by means of a closure member 13 which is preferably pocket or trough'shaped and which serves to receive the ashes and coke generated duringthe gas making operations. This member -13 which may be of any desiredconstruction, is, preferably, as shown, 'a pocket or trough shapedmetallic pan supported from the foundations l1 and having an opening 14,controlled by a suitable form of gate l5, in the bot-tom thereof,through which material within this ash pit may be withdrawn. Thisdischarging mechanism, as shown is coni nected to the lowest part of themember 13 and ash and coke therefore readily slide out of the dischargeopening when the gate is opened. rPhe arrangement is such that removalof the ash or coke inthe pit 13 may be the nature of a continuous of anysuit-able character,

readily accomplished without interruptiiig the continuous carrying on Ofthe'gas and coke making reactions. But if desired another type ofdischarge may be used-any of the well known types of fuel feeders whichare capable 4of'passing coal or the likel therethrough withoutpermitting substantial leakage of air or gas through the feeder, beingsuitable. C

The shell 10 isprovided, throughout partV of its height, with a lining20, which may be and is therefore shown diagrammatically. This lining ispreferably of firebrick, or other similar refractory material, and has acentrally arranged passage or chamber therein-which is constructed toreceive a. fuel bed of carbonaeeous material. AS shown this chamber hasits least diameter intermediate its upper and lower ends, the walls'deining the chamber being ared: outwardly toward'the bottom and thetop-thereof, as shown in the drawing. The lower .end of this chamber isclosed by means of a revolving grate designated generally by the numeral25, which is of less diameter than the lower open end of this chamber,this revolving grate 25 being surrounded by sections of grate designatedgenerally by the numeral 26, which sections of grate mav be of anysuitable and conventional character. consist of pivoted grate bars whicharevprovided with means, shown generally at 27, so constructed that theymay be actuated from outside the shell 10 to shake down the ashes 'Orfuel bed resting upon them.` Tlhe central grate 25 is preferably of thestepped form shown, the angle of inclination of one side of the gratebeing greater than the angleof inclination of the other side so that thevarious steps forming the grate are positioned eccentric -to the axis ofrotation of the grate as a. whole. Bymeans of this construction ofeccentric grate, rotation of the grate will cause a compacting of thefuel bed resting upon it and also suitable agitation or breaking up'ofthe coked mass of that fuel 'bed to permit of such compacting as willmaintain the bed of material substantially continuous throughout. Thegrate is prefer- As shown the sections of grate 26' ably mounted upon ahollow standard 28, which is connected to a steam supply pipe 29,

by means ofa' swivel coupling, designated generally by the vnumeral 80,which may be of any suitable type. The hollow standard 28 carries a gearwheel 3l, with which meshes a worm pinion 32, mounted upon a shaft 33driven from -any suitable source of power7 this construction being suchthat the grate 25 may be continuously rotated during operation of thedevice.`

Fuel is introduced into the` chamber by meansof fuel feeding mechanism85, which pas.sages 46` open into the chamber just below Ythe zone ofminimum diameter.' Also connected to the manifold 45.is a pipe 47, theother end of which opens into the bottom of a heat interchanger, orrecuperator 48, which is provided with a plurality of pipes 49, overwhich the gases passing through the pipe 47 into the heat interchangerflow, passing out through the pipe 50 which has positioned therein ablower or`pump 5l, of any suitable construction. The heat interchanger48 is provided at each end with achamher 52, into each of which each ofthe pipes 49 opens, one of these chambers 52beingconnected to theatmosphere through the opening 53, the other having'afgpipe54-,connccted thereto, which pipe opens into the manifold. 55, thisma-nifold.in turn being positioned adjacent the lower end ofthe chamber,and having a plurality of pipes -or passages 56 which open into thelower endof that chamber.V During oper- .4 ation 4`of the device thepump 51 willcreate a suction drawing the airthrough the opening 53,pipes 49, pipe 54, manifold 55 andpassages156 into the fuel bed withinthe lchamber whence it will pass upwardly along the wall or surface ofthe lining 20, and through any space which exists during operationbetween the outer zone of the fuel bed and the lining, the resultinggases passing out through the passages 46 into the manifold 45 andthence through the pipe 47and heat interchanger 48 and then out throughthe pipe 50 which connect-s to vent or stack. j Valves 57 and 58 arepositioned in the pipes 54 and 47 respectively to control flow throughthose pipes.

In the carrying on of thisl method a fuel bed of carbonaceous material,such as coal,

vbeing subjected to intense heat.

wehrte resulting from such blasting passing outwardly through the pipe'47, and heat interchanger 48 to the stack, or upwardly through theremainder ofthe fuel and 'thence outwardly through the oifta-ke pipe'40. Ubviously the relative proportion of these prod- 47 may be readilycontrolled by manipulating the valve 58, .within the offtake .47, tothuli` cause all orany desired proportion to pass upwardly and outthrough the pipe 40.

" This outer zone is designated, somewhat diagrammatically by the letterA, this Zone constituting in effect a cylinder or layer of highly heatedincandescent fuel, which surrounds the central portionor zone of thefuel.

bed, which is designated generally by the letter B. Because of the hightemperature which is maintained within this zone A heat vucts which passoff through the pipes 40 and l is transmitted therefrom, by radiationand,2

conduction, into the central portion B of the fuel bed. Fresh green fuelis introduced into the chamber through' the fuel feed-ers 35, thisportion of fuel being designated generally by the numeral C.. As theblasting of the Zone yA continues, with consequent development ofconsiderable quantities of heat, the fuel within the zone B is heatedand the volatile matter therein driven out to form incandescent coke,this coke, during rotation of the grate 25 being gradually fed over theedges of that grate and into the ash pit 13 whence it is removed,asdesired, through the opening- 14. Y

This is a particularly desirable method of making coke. It has been thegeneral prac- `tice heretofore in the manufacture of coke to utilizeretorts, constructed of some refractory material, which are soconstructed that the fuel to be coked is fed into the interior of theretort, the outside of the retort Obviously this methodis inelicientsince an excessive amount of heat must befused in order to raise thetemperature of the coal within the retorts sufficiently high to securethe desired coking action. This is true not only because of theresistance of the material of the retort .itself to the conduction ofheat therethrough,

but is probably even moredue to the fact that as the coal. is heated ittends to sh'rink away from the vwalls of the retort to greatly increaseVthe resistance to heat transfer into this coal. A second objection tothe conventional type. of coke oven retort is thatconlsiderabletemperature shockstend to break fuel in the zone lar inconstruction to the ordinary gas pro! ducer, and, therefore th'e dangerattendant upon shutting down the apparatus is entirely obviated, and itmay be shut down and st-arted up again at will. Furthermore because ofthe fact that the fuel bed is continuous throughoutV without any retortwalls separating the burning fuelfrom the fuel being-carbonized theefficiency of the device is considerably increased, the quantity of coalconsumed in the zone A perton of coke produced being-less than would betliecase with the conventional retort apparatus. The retort illustratedis Ycylindrical in form, but of course this general shape is notessential. But since the heat is transmitted into the central Zone Bprincipally by `conduction and radiation from the, fuel within Zone A,the thickness of the layer of materialin the zone B is quite limited. Ofcouise, where the gases generated within the lZone A pass upwardly alongthe 1lining 20 andout through thel pipe 4() they tend to highly heatthat lining and as a result the C wil'lbe heated by radiation from thisheated lining. If it is desired to increase the capacity of aretort,therefore, it would in practice be accomplished by mak- .ing the chamberwithin the retort rectangular, instead of cylindrical, and making correspondingchanges in the grate, blasting mechanism, discharge mechanism,etc., all of which changes are obvious ones.

But this form of apparatus not only lends itself to the carrying outof avery efficient and satisfactory method of producing coke, it alsopermits of at the same time producing a very useful and satisfactorytype of combustible gas` W'ith the ordinary coke oven retortacombustible gas is of course produced, this gas consistingof thevolatile material which is driven off. during the distillation of thecoal to form the coke. This gas is of a very high heat value, and whileit is of course avery good gaseous fuel, nevertheless it is ofunnecessarily high heat value and shouldy ordinarily be diluted. withsome other gas of lower heat value before it is used. The form ofapparatus described above lends itself particularly to the production ofa combustible gas which is of very desirable character.- The zone Bbeing incandescent is in such condition that if steam is passed incontact therewith chissa@ Win be broken down aad 'hydrogen and carbonmonoxide will-tbe produced,'1n other words so called. water-gas pipe.29, which -is connected tov the hollow standard 28 by means of theswivel joint 80 is also connected to a suitable'source of supply'ofsteam which may be introduced, under pressure; into the fuel within thezone B, through suitable openings within the grate 25. These openingsvare notv specifically shown, but lthe grate25 is of conventionaldesign, servingboth as a grate to support` the fuel bed, and also asablast tuyre through which steam under pressure is introduced into thefuel resting upon it.. As this steam is introduced into the fuel .withinthe zone B,

'and comes in contact with that incandescent Y .fuel it is decomposedand forms a gas consistingf essentially of hydrogen and carbon-monoxide.Of coursethe temperature of this gas is quite high and as it passesupwardly through the fresh or green fuel in the zone C it heats thatfuel and causes an initial dise tillation of thevvolatile hydrocarbontherein vto form so called coal gas, which mixes with the water gas andcarburates it, or increases y its -lieat value. The resulting mixed gaspasses off through the'oiftake pipe 40 to'any desired place of use orstorage. By properly lcontrolling the quantity of steam with which thevincandescent coke in the lower portion of the zone B is blasted, throughmanipulation 'of the valve 34, or in any other way, the rela-- tiveproportions of watergas and coal gas may be controlled to give a gas ofdesired heat value.

1 By properly manipulating the valve 57 the blasting of the-outer zone Amay be controlled to effect complete combustion of the fuel within thatzone, orto generate producer gas; And, as stated above, by properlymanipulating the valve 58 all, or any desired fraction, of this gas maybe caused-to pass off through the pipe 47, or all, or any fraction, ofit may be admixed with the water gas and coal. gas evolved within thezones B and C, to dilute those admixed gases, the resulting diluted gaspassing off through vthe pipe 40. Thus a gas of any desired'heat valueover a wide range may be secured-this gas, as desired, consisting ofcoal gas, coal gaswater gas, coal gas-producer gas, coal gaswatergas-producer gas, or, where coke, or the like is used as fuel instead ofa material having volatile hydrocarbons therein, then water gas alone,lor a mixed water gas and producer gas maybe obtained. Consequently Ywill begenerated.' .As described above the i As Will be noted the pipe4T, Where it opens into t-he hottolnof the heat interchangcr 48, isprovided with a burner element 60, which `is covered over by refractorymaterial 6l.

'Certain refractory materials, such as fire brick, act as catalysts, andwill cause to freely burn a mixture of air and a combustible.

gas 'which is'so leanfthat it will not under normalconditions burn atall. During operation of this apparatus even When the Zone A is beingblasted to; complete combustion, the gas resulting from the reactionsWithin that zone Will generally be, in fact, a poor producer gas, withaneXcess of air. Because; of the `leanness of the mixture this gas wouldprobably not burn .under normal conditions, but when it is brought intocontact With the refractory material 6l, at high temperature,"

' lit is just as applicable to other carbonaceous fuels. n

While themethod herein described, and the form of apparatus for carryingthis method into-eifect, constitute preferred `embodiments of theinvention, it is to be understood that the-invention is not limited tothis precise method or this precise form of apparatus, and that`chan-ges may be made in either- Without departing from the scope of theinvention which is defined in the appended claims.

What is claimed is:

1. In the distillation of solid carb'onaceous material, so as togenerate a combustible gas and alsoproduce coke, in which asubstantially continuous charge of the material being distilled ismaintained Within a retort, the method which comprises blasting 'theouter zone ofv said .charge of ignited material with air toincandescence to generate heat for raising the temperature of theContiguous central zone of said-material to cause the driving off of thevolatile constituents therefrom; and concomitantly blastingwith steamthe 4material Within the central zone .from which thelvolatileconstituents have been evolved.

2. In the distillation of solid carbonaceous material, so as to generatea combustible gas and produce coke, in which a substantially continuouscharge of the material being distilled is maintained Within a retort,the method which comprises blasting the outer Zone of said charge ofignited material With air to incandescence to generate heat for raisingi the temperature of the contiguous central zone of said material tocause the driving off off from the fuel Within the central zone;'

and removing at another point products of combustion resultingfrom theblasting of the outer zone of said charge of material.

. rfhe method of continuously generating combustible gas including Watergas which comprises maintaining a substantially con tinuous fuel bed ofsolidcarbonaceous material Within a generating chamber5'blastiiig lonezone of said bed of ignited material With air to incandescence; heatingthe remaining contiguous portion of said bed of material by conductionand radiation from said incandescent zone to raise the said remainingportion of said fuel bed to incandescence; and continuously blasting thesaid remaining portion of the fuel bed with steam to effect thegeneration of Water gas. e

'4. The method of continuously generating combustible gas includingWater gas Which comprises maintaining a substantially continuous fuelbed of solid carbonaceous material Within a generating chamber, blastingthe outer Zone of said bed of ignited material with air to effectcombustion thereof to thus generate heat to maintain the contiguouscentral Zone of said bed of material in incandescence;

continuously blasting the said central `zone With steam to effect thegeneration of Water gas; removing at one point products of thecombustion formed in the outer zone of said fuel bed, and removing atanother point generated Water gas formed in the central Zone of the fuelbed.

5. The method of producing combined Water gas andl coal gas Whichcomprises maintaining. a substantially continuous bed of solidcarbona'ceous material Within a retort, blasting the outer zone of saidbed of ignited carbonaceous material With air to effect com bustionthereof to thus generate heat for distilling the volatile constituentsfrom the ma- .terial Within the contiguous central zone of said. bed tocarbonize said `material and for heating such materialtoincandescence;blasting the incandescent material Within said central zone with steamto effect the generation of Water gas, removing the carbonized materialfrom the bottom ofsaid bed and introducing fresh solid carbonaceousmaterial tolbe carbonized on top of said bed, passing highly heatedWater gas upwardly through v the fresh fuel upon the top of the centralZone to assist in' distilling the volatile constituents from the fuelWithin said upper part of the central zone; removing at one pointproducts resulting from the combustion in the outer within a retort,blasting the outer Zone of saidignited fuelbed with air to generateproducer gas and to, at the same time, raise the temperature of saidouter zone to heat the material within the contiguous-central zone ofsaid fuei bed to effect distillation of thatportion of the fuel which isin the central Zone to drive off the volatile constituents therefrom tocarbonize said fuel and to raisethe result ing carbonized fuel withinthe lower portion of said central zone to incandescence; concomitantlyblasting the carbonized fuel within the said lower portion of thecentral zone of the fuel bed with steam to effect the generation ofwater gas, and passing the water gas and the producer gas generated inthe'said outer Zone upwardly through the fuel within' the upper portionof the fuel bed to effect driving olf of the volatile constituents fromthat fuel.

7. The method of continuously producing a combined coal gas,^water gas,and producer gas which comprises maintaining a .substan' tiallycontinuous fuel bed of solid carbonaceous material within a retort,blasting the outer Zone of said ignited fuel bed with air to generateproducer gas and to, at the same time, raise the temperature of saidouter zone to heat the material lwithin the contiguous central'zone ofsaid fuel bed to effect distillation of that portion of the fuel whichis in the central zone to drive off the volatile constituents therefromto 'carbonize said fuel and to raise the resulting carbonized fuelwithin the said central zone to incandescence; concomitantly blastingthe carbonized fuel within the said central portion of the fuel bed withsteam to effect Athe generation of water gas, passing the water gas andthe producer gas generated in the said outer zone, upwardly through thefuel within the upper lportion of the fuel bed to effect further drivingoff of the volatile constituents from that fuel; 4removing the ashresulting from the blasting of the outer zone to generate producer gas,and the coke resulting from the carbonizing action within the lcentralzone, from the lower portion of said fuel bed and adding fresh fuel tothe upper portion of said fuel bed to take the place of the materialremoved from the lower portion of said bed.

8. The method of continuously generating a combustible gas comprisingwater gas and producer gas which comprises maintaining a substantiallycontinuous bed of solid carbonaceous materialwithin a generatingchamber,

blasting one ignited zone of said bed of material with air to generateproducer gas and to raise the temperature of said one zone toincandescence; heating the remaining contiguous portion of said bed toincandescence, by conduction and radiation from said incandescent zone;concomitantly blasting the incandescent material within the saidi'emaining portion of the fuel bed with steam to effecttlie generationof water gas, and withdrawing generated-producer gas and water gastogether.

9. The methodl of generating a gas of controlled heat value fromcarbonaceous material, which' comprises maintaining a substantiallycontinuous fuel bed of solid carbonaceous material within a retort,blasting one ignited zonev of said bed with air to incandescence;heating the remaining contiguous zone of said fuel bed by conduction andradiation 'to distil-l off volatile constituents from the materialwithin said remaining zone, to produce coke and to raise the temperatureof said coke to `incand`escenceg concomitantly blasting the incandescentcoke with steam to generate water gas; admiXing. generated water gas anddistilled volatile constituents, withdrawing at one point products ofthe combustion formed in the one zone of the bed of material,withdrawing at another point admixed water gas and distillation productsformed in the remaining contiguous ,zone of the fuel bed; andvcontrolling the steam blast to vary the generation of water gas to,thus give a combustible gas of controlled heat value.

10. The method of making gas of con# trolled heat value from so-lidcarbonaceous material, which comprises maintaining a substantiallycontinuous fuel bed of carbonaceous material within a retort, blastingthe outer ignited zone of said fuel bed with air to generate producergas, and to raise the temperatureV of said outer Zone of the fuel bed toincandescence; heating the contiguous central portion of the fuel bed byconduction and radiation from the said outer zone, to distill off thevolatile constituents from the fuel within the said central portion ofthe fuel bed, to generate coke and to raise lthe temperature .of saidgenerated coke to incandes- 'cence; concomitantly blasting saidincandesing said fuel bed; an otake pipe leading off from the upper endof said retort; asecond o iftake pipe leading o from about the perlpheryof the fuel bed within said, retort a substantial distance below thesaidv first named offtake pipe; means for operating the said grate tocause removal from the fuel bed Within the retort ofthe carbonizedmaterial resting upon that grate, means for introducing fuel into saidretort to take the place of the carbonized fuel removed therefromthrough the said grate; means for introducing a blast of air into theouter' zone of said fuel bed adjacent the wall of the retort to maintainsaid outer zone in a state of incandescence to heat the contiguouscentral zone ofthe fuel bed and drive off the volatile constituents fromthe fuel within said central zone; and means for concomitantly blastingI the resulting carbonized fuel within the central zone of the fuel bedwith steam,lthe posiltioning of the two said olftake pipes being suchthat evolved volatile products 'and products resulting from blasting-thecarbonized fuel within the central zone of said fuel bed will pass offthrough the first named oiftake pipe and products of combustionresulting from blasting the outer zone of the fuel bed with air Willvpass off through the second named pipe. y

which carbonizinof of a substantially continuous bed ofmaterlalisaccomplished by blasting the outer zone of said material to generatesuflicient' heat to carbonize the contiguous central zone of saidbed ofmaterial, comprising a shell having a carbonizing chamber therein, arefractory lining for said shell, the inner Wall of said lining within.which the combustion of the outer zone of the bed of material takesplace being upwardly tapered; a grate/for supporting said bed ofmaterial,

` comprising plvoted grate bars operable from outside the shell andadapted to support the outer zone of the said bed of material, and arotary eccentric grate having means for cotinuously rotating said grateduring operation of said device and positioned for supporting thecentral zone of material.

13. A retort of the character described, in which carbonizing of. asubstantiallycontinuous bed of material is accomplishedby blasting theouter zone of said material to generate the said bed of bed of materialwith air to effect combustion thereof; and means for concomitantlyblastlcomprising a shell having aV carbonizing chamber therein andadapted to contain a substantially continuous bed of solidcarbonaceousmaterial to be carbonized, a refracj' tory lining for said shell, meansfor introducing a blast only into the zone of material adjacent theliningof thesaid shell toefi'ect combustion of the outer zone of the bedof material, and offtake forthe products of combustion formedin saidouter zone 0f the hed of material, the inner wall of said re-' fractorylining within Which the'combustion of the outer zone iolf the bed ofmaterial takes place being upwardly tapered substantially gf,'throughout the extentv of said zone, whereby the blast is confined tosaid outer zone of the material andthe contiguous-central zone of thematerial is carbonized by vradiation and conduction of heat from saidouter zone.

` 15. A retort of the character described, comprising a shell having acarbonizing chamber therein andA adapted to contain a substantiallycontinuous bed of solid car- 12. A retort of the vcharacter descrlbed,1n

bonaceous material to be `carbonized, a regr,- fract'ory lining for saidshell, means for introducing a blast only into the zoneof niaterialadjacentthe lining o f the-said shell, an oiftake for the products ofcombustion formed in said outer zone of the bed of Ina- ,un terial, theinner wall of said lining within which the combustion of the outer ZoneofA the bed of material vtakes place being up- Wardly taperedsubstantially throughout the extent of said zone,.whereby the blast isconmy, fined to the outer zone of the bed of material and the contiguouscentral zone of the material is carbonized by radiation and conductionof heat therefrom, and a rotary grate for supporting the bed of materialWithin the 1m carbonizing chamber, said grate'being adapted to effectcompacting of the material Within the said tapered 4portion of the saidchamber.

In testimony whereof I hereto aHiX my sig- H 5 nature.

HARRY F. SMITH,

sufficientv heatto carbonize Athe contiguous central zone of said bed ofmaterial, comprisingl a shell `having a carbonizing chamber therein, arefractory lining for said shell, the inner wall of said lining withinwhich the combustion of the outer zone of thebed f material takes placebeing upwardly tapered; a grate for supporting the outer zone of thesaid bed of material, and a. grate supporting the central zone of thematerial, means for separately operating the said1 two grates; means forblasting the said outer zone of the

